Patent US3824037A successfully refreshed from Google Patents.
US3824037A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Suspension of rotor blades on the rotor head of a rotorcraft without the use of flapping or drag hinges
Assignee: Airbus Defence and Space GmbH
•
Filing: 1972-10-06
•
Granted: 1974-07-16
•
Expires: 1992-10-06
Abstract
Abstract Vibration-free and wobble-free suspension of rotor blades in the rotor head of a helicopter. The invention is applicable to blade suspensions wherein the blades are received into a blade-base holding sleeve and same is then mounted on a central member in the rotor head through a compact bundle of elastic lamellae which are arranged parallel to the rotating plane of the rotor and whose radially inner ends are connected to a pin fixed in the central member and coaxially with the rotor axis. In the present invention there is additionally provided bands of stiffly resilient material encircling the central member and further similar bands are arranged around the holding sleeve. Thus, in case of breakage of the central member the rotor blade will not only be temporarily held in operational position but will be permitted to move radially outwardly sufficiently to slightly unbalance the rotor and thereby give the pilot warning of the occurrence of damage. On the sleeves holding the base of the blade, the resilient bands will in the event of breakage hold the parts in operating relationship for a sufficient period of time to maintain the rotor operational until the break is presumably discovered on a routine inspection.
Inventors
- 👤 A Schwarz
- 👤 K Mautz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:21
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/37; B64C27/45; B64C27/327
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
251 words
In a suspension device for a plurality of rotor blaDes on rotor head means of a rotorcraft which is devoid or flapping and drag hinges in the connection between said rotor blades and said rotor head means, said suspension device having a rotatable rotor shaft supporting said rotor head means for rotation therewith, said plurality of elongated blades being mounted on said rotor head means and extending radially outwardly therefrom, support means for supporting each of said plurality of elongated rotor blades for rotational movement about an axis parallel to the longitudinal axis of said rotor blades and a plurality of nonextensible, torsionally and elastically deformable members for securing said rotor head means to each of said rotor blades, the improvement comprising: at least one central dislike member mounted on said rotor head means coaxial with the axis of rotation thereof and being rotatable therewith, said central member including means for permitting a connection to each of said nonextensible, torsionally and elastically deformable members; and elastic band means encircling said central dislike member to retain said central dislike member in an operating condition if said central dislike member should break during usage thereof, said broken central dislike member, and said elastic band means, during a rotation thereof, imparting one of a purposeful imbalance to said suspension device to thereby warn a pilot of the occurrence of a broken component in said suspension device and an insignificant amount of imbalance so that said breakage will be detected during inspection of said rotorcraft.
Claim 2
Dependent Claim
251 words
In a suspension device for a plurality of rotor blaDes on rotor head means of a rotorcraft which is devoid or flapping and drag hinges in the connection between said rotor blades and said rotor head means, said suspension device having a rotatable rotor shaft supporting said rotor head means for rotation therewith, said plurality of elongated blades being mounted on said rotor head means and extending radially outwardly therefrom, support means for supporting each of said plurality of elongated rotor blades for rotational movement about an axis parallel to the longitudinal axis of said rotor blades and a plurality of nonextensible, torsionally and elastically deformable members for securing said rotor head means to each of said rotor blades, the improvement comprising: at least one central dislike member mounted on said rotor head means coaxial with the axis of rotation thereof and being rotatable therewith, said central member including means for permitting a connection to each of said nonextensible, torsionally and elastically deformable members; and elastic band means encircling said central dislike member to retain said central dislike member in an operating condition if said central dislike member should break during usage thereof, said broken central dislike member, and said elastic band means, during a rotation thereof, imparting one of a purposeful imbalance to said suspension device to thereby warn a pilot of the occurrence of a broken component in said suspension device and an insignificant amount of imbalance so that said breakage will be detected during inspection of said rotorcraft.
Claim 3
Dependent Claim
126 words
The improvement according to claim 1, wherein said support means for each of said elongated rotor blades includes means defining an opening therein spaced radially outwardly from said rotor head means, said rotor blade having a pin thereon adapted to be received in said opening and further elastic band means encircling said means defining said opening to retain said means in an operating condition if said means should break during usage thereof, said means, when broken, and said further elastic band means imparting one of a purposeful imbalance to said suspension device to thereby warn a pilot of the occurrence of a broken component in said suspension device and an insignificant amount of imbalance so that said breakage will be detected during inspection of said rotorcraft.
Claim 4
Dependent Claim
42 words
The improvement according to claim 2, wherein said means defining said opening has a plurality of recesses in the periphery thereof to encourage breakage to occur at the location of said recesses to isolate the breakage from said further elastic band means.
Claim 5
Dependent Claim
17 words
The improvement according to claim 2, wherein said further elastic band means consists of a fiber-reinforced plastic.
Claim 6
Dependent Claim
19 words
The improvement according to claim 2, wherein said further elastic band means consist of steel wire or boron fibers.
Claim 7
Dependent Claim
27 words
The improvement according to claim 5, wherein each of said elastic bands is secured by a further band of an elastomer on a silicone or polyurethane base.
Claim 8
Dependent Claim
40 words
The improvement according to claim 1, wherein said central disklike member has a plurality of recesses in the periphery thereof to encourage breakage to occur at the location of said recesses to isolate the breakage from said elastic band means.
Claim 9
Dependent Claim
17 words
The improvement according to claim 1, wherein said further elastic band means consists of a fiber-reinforced plastic.
Claim 10
Dependent Claim
19 words
The improvement according to claim 1, wherein said further elastic band means consist of steel wire or boron fibers.
Claim 11
Dependent Claim
231 words
In a suspension device for a plurality of rotor blades on rotor head means of a rotorcraft which is devoid of flapping and drag hinges in the connection between said rotor blades and said rotor head means, said suspension device having a rotatable rotor shaft supporting said rotor head means for rotation therewith, said plurality of elongated blades being mounted on said rotor head means and extending radially outwardly therefrom, support means for supporting each of said plurality of elongated rotor bLades for rotational movement about an axis parallel to the longitudinal axis of said rotor blades and a plurality of nonextensible, torsionally and elastically deformable members for securing said rotor head means to each of said rotor blades, the improvement comprising: means defining an opening in said support means for each of said elongated rotor blades, said rotor blades each having pin means thereon adapted to be received in said opening and elastic band means encircling said means defining said opening to retain said means in an operating condition if said means should break during usage thereof, said means, when broken, and said elastic band means imparting one of a purposeful imbalance to said suspension device to thereby warn a pilot of the occurrence of a broken component in each suspension device and an insignificant amount of imbalance so that said breakage will be detected during inspection of said rotorcraft.
Claim 12
Dependent Claim
231 words
In a suspension device for a plurality of rotor blades on rotor head means of a rotorcraft which is devoid of flapping and drag hinges in the connection between said rotor blades and said rotor head means, said suspension device having a rotatable rotor shaft supporting said rotor head means for rotation therewith, said plurality of elongated blades being mounted on said rotor head means and extending radially outwardly therefrom, support means for supporting each of said plurality of elongated rotor bLades for rotational movement about an axis parallel to the longitudinal axis of said rotor blades and a plurality of nonextensible, torsionally and elastically deformable members for securing said rotor head means to each of said rotor blades, the improvement comprising: means defining an opening in said support means for each of said elongated rotor blades, said rotor blades each having pin means thereon adapted to be received in said opening and elastic band means encircling said means defining said opening to retain said means in an operating condition if said means should break during usage thereof, said means, when broken, and said elastic band means imparting one of a purposeful imbalance to said suspension device to thereby warn a pilot of the occurrence of a broken component in each suspension device and an insignificant amount of imbalance so that said breakage will be detected during inspection of said rotorcraft.
Claim 13
Dependent Claim
25 words
The improvement according to claim 10, wherein said elastic band is secured by a further band of an elastomer on a silicone or polyurethane base.
References Cited (Backward Citations)
GB1190259A
Cited
US3545880A
Cited
US3591310A
Cited
US3610774A
Cited
US3679322A
Cited
US3625634A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-15 | 1978-01-14 | 1978-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-15 | 1982-01-14 | 1982-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-15 | 1986-01-14 | 1986-07-16 | $7700.00 | Window Closed / Lapsed |